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Scientific Applications of the AHP Method in Transport Problems

Podvezko V., Sivilevicius H., Podviezko A.

Archives of Transport

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2014

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Vol. 29, iss. 1

47--54

EN

In methodologies of solving different transport problems where the best decision has to be determined usually a number of chosen quantitative criteria are incorporated, which describe qualitative parameters of transport systems in quantitative terms. Often weights which reveal importance of such criteria must be evaluated. The realm of proprietary methods used in engineering sampling and experimental studies does not comprise methods of weight evaluation. Consequently, expert evaluation methods, which elicit weights of criteria from experienced, qualified and fair experts, are used. Among the most popular such methods is the method AHP (Analytic Hierarchy Process). Scientists of Vilnius Gediminas Technical University used this method for investigation of interrelationship of elements of a transport system; for evaluation of influence of the interrelationship on road traffic safety; and for evaluation of quality of passenger railway transportation service.

2

Effect of reclaimed asphalt pavement gradation variation on the homogeneity of recycled hot-mix asphalt

Vislavicius K., Sivilevicius H.

Archives of Civil and Mechanical Engineering

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2013

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Vol. 13, no. 3

345--353

EN

Now, flexible pavement, made of hot-mix asphalt with the addition of the reclaimed asphalt pavement granules in the central asphalt mixing plant, is increasingly used. The amount of the added reclaimed asphalt pavement depends on mineral materials and their homogeneity. The article presents the algorithm for predicting the composition of mineral constituent of recycled hot-mix asphalt, taking into consideration the variation of gradation of all mineral materials and reclaimed asphalt pavement, in the absence of random batching errors. When simulating, the gradations of the reclaimed asphalt pavement and mineral materials are selected by using a random number generator. The example of simulation is presented and the results obtained are analyzed.

3

Finite element simulation of the normal interaction of particles in the visco-elastic solid

Rimsa V., Kacianauskas R., Sivilevicius H.

Mechanics and Control

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2011

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Vol. 30, no. 4

245-253

EN

This paper addresses the 3D FE simulation of the normal interaction of stiff but deformable particles in binder matrix on the meso-scale. The particles are assumed to be elastic spheres while matrix is considered as viscoelastic solid. The investigation is aimed to capture interaction in terms of normal forces under tension. The problem is considered by applying geometrically linear and nonlinear approaches. Results illustrate influence of initial interparticle gap reduction of which yields significant increase of the interaction force. Comparison between purely elastic and viscoelastic solutions is also presented.

PL

Niniejszy artykuł dotyczy trójwymiarowej symulacji metodą elementów skończonych oddziaływania w kierunku normalnym sztywnych, ale odkształcalnych cząstek w spoistej osnowie na poziomie mezoskopowym. Cząstki są traktowane jako sprężyste kule, zaś osnowa jako ciało lepkosprężyste. Badania mają na celu znalezienie sił oddziaływania pod obciążeniem. Zagadnienie jest rozpatrywane przy zastosowaniu modelu geometrycznie liniowego i nieliniowego. Wyniki pokazują wpływ wstępnego zmniejszenia odstępu na znaczący wzrost siły oddziaływania. Przedstawione jest również porównanie między rozwiązaniem sprężystym i lepkosprężystym.